Advanced Electrical Installation Work 5th Edition
Advanced Electrical Installation Work
To Joyce, Samantha and Victoria
Advanced Electrical
Installation Work
FIFTH EDITION
TREVOR LINSLEY
Senior Lecturer
Blackpool and The Fylde College
AMSTERDAM • BOSTON • HEIDELBERG • LONDON • NEW YORK • OXFORD
PARIS • SAN DIEGO • SAN FRANCISCO • SINGAPORE • SYDNEY • TOKYO
Newnes is an imprint of Elsevier
Newnes
An imprint of Elsevier
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30 Corporate Drive, Burlington, MA 01803
First published by Arnold 1998
Reprinted by Butterworth-Heinemann 2001, 2002, 2003 (twice), 2004 (twice)
Fourth edition 2005
Fifth edition 2008
Copyright © 2008, Trevor Linsley. Published by Elsevier Ltd. All rights reserved
The right of Trevor Linsley to be identified as the author of this work has been asserted in accordance with the
Copyright, Designs and Patents Act 1988
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Whilst the advice and information in this book is believed to be true and accurate at the date of going to press, neither the
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Contents
Preface
vii
Acknowledgements
ix
UNIT 1 – Application of health and safety and electrical principles
1
Chapter 1 Statutory regulations and safe working procedures
3
Chapter 2 Safe working practices and emergency procedures
51
Chapter 3 Effective working practices
77
Chapter 4 Electrical systems and components
95
Chapter 5 Electricity supply systems, protection and earthing
181
Chapter 6 Electrical machines and motors
227
UNIT 2 – Installation (buildings and structures): inspection, testing and commissioning
251
Chapter 7 Safe, effective and efficient working practices
253
Chapter 8 Inspection, testing and commissioning
311
UNIT 3 – Installation (buildings and structures): fault diagnosis and rectification
347
Chapter 9 Fault diagnosis and repair
349
Chapter 10 Restoring systems to working order
373
Answers to Check your understanding
381
Appendix A: Obtaining information and electronic components
383
Appendix B: Abbreviations, symbols and codes
385
Glossary of terms
387
Index
397
v
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Preface
The 5th Edition of Advanced Electrical Installation Work has been completely rewritten in 10 Chapters to closely match the 10 Outcomes of the
City and Guilds qualification. The technical content has been revised and
updated to the requirements of the new 17th Edition of the IEE Regulations
BS 7671: 2008. Improved page design with new illustrations gives greater
clarity to each topic.
This book of electrical installation theory and practice will be of value to
the electrical trainee working towards:
●
●
●
●
The City and Guilds 2330 Level 3 Certificate in Electrotechnical
Technology, Installation Route.
The City and Guilds 2356 Level 2 NVQ in Installing Electrotechnical
Systems.
The SCOTVEC and BTEC Electrical Utilisation Units at Levels II and
III.
Those taking Engineering NVQ and modern Apprenticeship
Courses.
Advanced Electrical Installation Work provides a sound basic knowledge of
electrical practice which other trades in the construction industry will find
of value, particularly those involved in multi-skilling activities.
The book incorporates the requirements of the latest Regulations,
particularly:
●
17th Edition IEE Wiring Regulations.
●
British Standards BS 7671: 2008.
●
Part P of the Building Regulations, Electrical Safety in Dwellings:
2006.
●
Hazardous Waste Regulations: 2005.
●
Work at Height Regulations: 2005.
Trevor Linsley
2008
vii
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Acknowledgements
I would like to acknowledge the assistance given by the following manufacturers and professional organizations in the preparation of this book:
●
●
The Institution of Engineering and Technology for permission
to reproduce Regulations and Tables from the 17th Edition IEE
Regulations.
The British Standards Institution for permission to reproduce material from BS 7671: 2008.
●
Crabtree Electrical Industries for technical information and data.
●
RS Components Limited for technical information and photographs.
●
Stocksigns Limited for technical information and photographs.
●
●
Wylex Electrical Components for technical information and
photographs.
Jason vann Smith MIET MiEEE MBCS MACM for the photographs
used in the page design.
I would like to thank the many College Lecturers who responded to the
questionnaire from Elsevier the publishers, regarding the proposed new
edition of this book. Their recommendations have been taken into account
in producing this improved 5th Edition.
I would also like to thank the editorial and production staff at Elsevier the
publishers for their enthusiasm and support. They were able to publish
this 5th Edition within the very short timescale created by the publication
of the 17th Edition of the IEE Regulations.
Finally I would like to thank Joyce, Samantha and Victoria for their support
and encouragement.
ix
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Ch 1
Statutory regulations and
safe working procedures
3
U
V
W
Unit 1 - Application of health and safety and electrical principles – Outcome 1
Underpinning knowledge: when you have completed this chapter you should be able to:
●
●
●
6
identify the Safety Regulations relevant to the electrotechnical industry
6
6
identify environmental legislation relevant to the electrotechnical industry
C1
state employer and employee responsibilities
●
state the human and environmental conditions leading to workplace accidents
●
describe a procedure for reporting accidents
●
recognize workplace safety signs
●
carry out a risk assessment
●
list the changing work patterns within the industry
2
L1
2
L2
2
L3
To 3 phase supply
C1
2
C3
4
5
6
Advanced Electrical Installation Work
Introduction
This first chapter of Advanced Electrical Installation work covers the health
and safety core skills required by the City and Guilds Level 3 Certificate
in Electrotechnical Technology. That is the Health and Safety Laws and
Regulations that underpin the electrotechnical industry.
Let me begin by looking at the background to the modern Health and
Safety Regulations and the electricity supply and wiring regulations.
Electricity generation as we know it today began when Michael Faraday
conducted the famous ring experiment in 1831. This experiment, together
with many other experiments of the time, made it possible for Lord Kelvin
and Sebastian de Ferranti to patent in 1882 the designs for an electrical
machine called the Ferranti–Thompson dynamo, which enabled the generation of electricity on a commercial scale.
4
In 1887 the London electric supply corporation was formed with Ferranti
as chief engineer. This was one of the many privately owned electricity
generating stations supplying the electrical needs of the United Kingdom.
As the demand for electricity grew, more privately owned generating stations were built until eventually the government realized that electricity
was a national asset which would benefit from nationalization.
In 1926 the Electricity Supply Act placed the responsibility for generation in
the hands of the Central Electricity Board. In England and Wales the Central
Electricity Generating Board (CEGB) had the responsibility for the generation
and transmission of electricity on the supergrid. In Scotland, generation was
the joint responsibility of the North of Scotland Hydro-Electricity Board and
the South of Scotland Electricity Board. In Northern Ireland electricity generation was the responsibility of the Northern Ireland Electricity Service.
In 1988 Cecil Parkinson, the Secretary of State for Energy in the Conservative
government, proposed the denationalization of the electricity supply industry; this became law in March 1991, thereby returning the responsibility
for generation, transmission and distribution to the private sector. It was
anticipated that this action, together with new legislation over the security
of supplies, would lead to a guaranteed quality of provision, with increased
competition leading eventually to cheaper electricity.
During the period of development of the electricity services, particularly in
the early days, poor design and installation led to many buildings being damaged by fire and the electrocution of human beings and livestock. It was the
insurance companies which originally drew up a set of rules and guidelines
of good practice in the interest of reducing the number of claims made upon
them. The first rules were made by the American Board of Fire Underwriters
and were quickly followed by the Phoenix Rules of 1882. In the same year the
first edition of the Rules and Regulations for the Prevention of Fire Risk arising from Electrical Lighting was issued by the Institute of Electrical Engineers.
The current edition of these regulations is called the Requirements for
Electrical Installations, IEE Wiring Regulations (BS 7671: 2008), and since
Statutory regulations and safe working procedures
July 2008 we have been using the 17th edition. All the rules have been
revised, updated and amended at regular intervals to take account of modern developments, and the 17th edition brought the UK Regulations into
harmony with those of the rest of Europe.
The laws and regulations affecting the electrotechnical industry have
steadily increased over the years. There is a huge amount of legislation
from the European law-makers in Brussels. These laws and regulations
will permeate each and every sector of the electrotechnical industry and
reform and modify our future work patterns and behaviour.
In this section I want to deal with the laws and regulations that affect our
industry under three general headings because there are a large number of
them, and it may help us to appreciate the reasons for them.
(i) First of all I want to look at the laws concerned with health and
safety at work, making the working environment safe.
(ii) Then I want to go on to the laws that protect our environment
from, for example, industrial waste and pollution.
(iii) Finally, I will look at employment legislation and the laws which
protect us as individual workers, people and citizens in Chapter 3
of this book.
The Health and Safety at Work Act 1974
Many governments have passed laws aimed at improving safety at work but
the most important recent legislation has been the Health and Safety at Work
Act 1974. The purpose of the act is to provide the legal framework for stimulating and encouraging high standards of health and safety at work; the act
puts the responsibility for safety at work on both workers and managers.
The Health and Safety at Work Act is an ‘Enabling Act’ that allows the
Secretary of State to make further laws, known as regulations, without
the need to pass another Act of Parliament. Regulations are law, passed
by Parliament and are usually made under the Health and Safety at
Work Act 1974. This applies to regulations based on European directives
as well as new UK Regulations. The way it works is that the Health and
Safety at Work Act established the Health and Safety Commission (HSC)
and gave it the responsibility of drafting new regulations and enforcing
them through its executive arm known as the Health and Safety Executive
(HSE) or through the local Environmental Health Officers (EHO). The
HSC has equal representation from employers, trade unions and special interest groups. Their role is to set out the regulations as goals to be
achieved. They describe what must be achieved in the interests of safety,
but not how it must be done.
Definition
Under the Health and Safety at Work Act an employer has a duty to care for
Under the Health and Safety at Work the health and safety of employees (Section 2 of the Act). To do this he has
Act an employer has a duty to care for a responsibility to ensure that:
the health and safety of employees.
●
the working conditions and standard of hygiene are appropriate;
5
Advanced Electrical Installation Work
Safety First
●
the plant, tools and equipment are properly maintained;
●
safe systems of work are in place;
Laws
The Health and Safety at Work Act
provides the legal framework for stimulating and encouraging health and
safety at work. It is:
●
the most important,
●
the most far reaching,
●
single piece of legislation.
●
safe methods of handling, storing and transporting goods and materials are used;
●
there is a system for reporting accidents in the workplace;
●
the company has a written Health & Safety Policy statement;
●
Definition
●
the necessary safety equipment – such as personal protective equipment (PPE), dust and fume extractors and machine guards – are
available and properly used;
the workers are trained to use equipment and plant safely.
Employees have a duty to care for
their own health and safety and that Employees have a duty to care for their own health and safety and that of
of others who may be afected by others who may be affected by their actions (Section 7 of the Act). To do
their actions.
this they must:
6
●
●
●
take reasonable care to avoid injury to themselves or others as a
result of their work activity;
co-operate with their employer, helping him or her to comply with
the requirements of the act;
not interfere with or misuse anything provided to protect their
health and safety.
Failure to comply with the Health and Safety at Work Act is a criminal
offence and any infringement of the law can result in heavy fines, a prison
sentence or both.
ENFORCEMENT
Laws and rules must be enforced if they are to be effective. The system
of control under the Health and Safety at Work Act comes from the HSE
which is charged with enforcing the law. The HSE is divided into a number of specialist inspectorates or sections which operate from local offices
throughout the United Kingdom. From the local offices the inspectors visit
individual places of work.
The HSE inspectors have been given wide-ranging powers to assist them in
the enforcement of the law. They can:
1. enter premises unannounced and carry out investigations, take
measurements or photographs;
2. take statements from individuals;
3. check the records and documents required by legislation;
4. give information and advice to an employee or employer about
safety in the workplace;
5. demand the dismantling or destruction of any equipment, material
or substance likely to cause immediate serious injury;
Statutory regulations and safe working procedures
6. issue an improvement notice which will require an employer to put
right, within a specified period of time, a minor infringement of the
legislation;
7. issue a prohibition notice which will require an employer to stop
immediately any activity likely to result in serious injury, and which
will be enforced until the situation is corrected;
8. prosecute all persons who fail to comply with their safety duties,
including employers, employees, designers, manufacturers, suppliers
and the self-employed.
SAFETY DOCUMENTATION
Under the Health and Safety at Work Act, the employer is responsible for
ensuring that adequate instruction and information is given to employees to make them safety-conscious. Part 1, Section 3 of the Act instructs all
employers to prepare a written health and safety policy statement and to
bring this to the notice of all employees. Your employer must let you know
who your safety representatives are and the new health and safety poster
shown in Fig. 1.1 has a blank section into which the names and contact
information of your specific representatives can be added. This is a large
laminated poster, 595 ⫻ 415 mm suitable for wall or notice board display.
FIGURE 1.1
New Health and Safety Law poster. Source: HSE © Crown copyright material is reproduced with the
permission of the Controller of HMSO and Her Majesty’s Stationery Office, Norwich.
7
Advanced Electrical Installation Work
All workplaces employing five or more people must display the type of
poster shown in Fig. 1.1 after 30 June 2000.
Safety First
Information
●
Have you seen the new Health
and Safety Law poster like Fig 1.1?
– in your place of work
8
– at the college.
●
Were the blank sections illed in?
To promote adequate health and safety measures the employer must
consult with the employees’ safety representatives. In companies which
employ more than 20 people this is normally undertaken by forming a
safety committee which is made up of a safety officer and employee representatives, usually nominated by a trade union. The safety officer is
usually employed full-time in that role. Small companies might employ
a safety supervisor, who will have other duties within the company, or
alternatively they could join a ‘safety group’. The safety group then shares
the cost of employing a safety adviser or safety officer, who visits each
company in rotation. An employee who identifies a dangerous situation
should initially report to his site safety representative. The safety representative should then bring the dangerous situation to the notice of
the safety committee for action which will remove the danger. This may
mean changing company policy or procedures or making modifications
to equipment. All actions of the safety committee should be documented
and recorded as evidence that the company takes seriously its health and
safety policy.
The Management of Health and Safety at Work
Regulations 1999
The Health and Safety at Work Act 1974 places responsibilities on employers to have robust Health and Safety systems and procedures in the workplace. Directors and managers of any company who employ more than
five employees can be held personally responsible for failures to control
health and safety.
The Management of Health and Safety at Work Regulations 1999 tell us that
employers must systematically examine the workplace, the work activity
and the management of safety in the establishment through a process of
‘risk assessments’. A record of all significant risk assessment findings must
be kept in a safe place and be available to an HSE inspector if required.
Information based on these findings must be communicated to relevant
staff and if changes in work behaviour patterns are recommended in the
interests of safety, then they must be put in place. The process of risk
assessment is considered in detail later in this chapter.
Risks, which may require a formal assessment in the electrotechnical
industry, might be:
●
working at heights;
●
using electrical power tools;
●
falling objects;
●
working in confined places;
●
electrocution and personal injury;
Statutory regulations and safe working procedures
●
working with ‘live’ equipment;
●
using hire equipment;
●
manual handling: pushing, pulling, lifting;
●
site conditions: falling objects, dust, weather, water, accidents and
injuries.
And any other risks which are particular to a specific type of work place or
work activity.
Provision and Use of Work Equipment Regulations 1998
These regulations tidy up a number of existing requirements already in place
under other regulations such as the Health and Safety at Work Act 1974, the
Factories Act 1961 and the Offices, Shops and Railway Premises Act 1963.
The Provision and Use of Work Equipment Regulations 1998 places a general
duty on employers to ensure minimum requirements of plant and equipment. If an employer has purchased good quality plant and equipment,
which is well maintained, there is little else to do. Some older equipment may
require modifications to bring it in line with modern standards of dust extraction, fume extraction or noise, but no assessments are required by the regulations other than those generally required by the Management Regulations
1999 discussed previously.
The Control of Substances Hazardous to Health
Regulations 2002
The original Control of Substances Hazardous to Health (COSHH)
Regulations were published in 1988 and came into force in October 1989.
They were re-enacted in 1994 with modifications and improvements, and
the latest modifications and additions came into force in 2002.
The COSHH Regulations control people’s exposure to hazardous substances in the workplace. Regulation 6 requires employers to assess the
risks to health from working with hazardous substances, to train employees
in techniques which will reduce the risk and provide PPE so that employees will not endanger themselves or others through exposure to hazardous
substances. Employees should also know what cleaning, storage and disposal procedures are required and what emergency procedures to follow.
The necessary information must be available to anyone using hazardous
substances as well as to visiting HSE inspectors.
Hazardous substances include:
1. any substance which gives off fumes causing headaches or respiratory irritation;
2. man-made fibres which might cause skin or eye irritation (e.g. loft
insulation);
3. acids causing skin burns and breathing irritation (e.g. car batteries,
which contain dilute sulphuric acid);
9
Advanced Electrical Installation Work
4. solvents causing skin and respiratory irritation (strong solvents are
used to cement together PVC conduit fittings and tube);
5. fumes and gases causing asphyxiation (burning PVC gives off toxic
fumes);
6. cement and wood dust causing breathing problems and eye
irritation;
7. exposure to asbestos – although the supply and use of the most hazardous asbestos material is now prohibited, huge amounts were
installed between 1950 and 1980 in the construction industry and
much of it is still in place today. In their latest amendments the
COSHH Regulations focus on giving advice and guidance to builders and contractors on the safe use and control of asbestos products.
These can be found in Guidance Notes EH 71.
Where PPE is provided by an employer, employees have a duty to use it to
safeguard themselves.
10
PPE at Work Regulations 1992
PPE is defined as all equipment designed to be worn, or held, to protect
against a risk to health and safety. This includes most types of protective
clothing, and equipment such as eye, foot and head protection, safety harnesses, life jackets and high-visibility clothing.
Under the Health and Safety at Work Act, employers must provide free of
charge any PPE and employees must make full and proper use of it. Safety
signs such as those shown in Fig. 1.2 are useful reminders of the type
of PPE to be used in a particular area. The vulnerable parts of the body
which may need protection are the head, eyes, ears, lungs, torso, hands
and feet and, additionally, protection from falls may need to be considered. Objects falling from a height present the major hazard against which
head protection is provided. Other hazards include striking the head
against projections and hair becoming entangled in machinery. Typical
methods of protection include helmets, light duty scalp protectors called
‘bump caps’ and hairnets.
Safety First
PPE
●
●
What type of PPE do you use at
work?
Make a list in the margin of the
book.
The eyes are very vulnerable to liquid splashes, flying particles and light
emissions such as ultraviolet light, electric arcs and lasers. Types of eye
protectors include safety spectacles, safety goggles and face shields. Screen
based workstations are being used increasingly in industrial and commercial locations by all types of personnel. Working with VDUs (visual display
units) can cause eye strain and fatigue and, therefore, work patterns should
be varied and operators are entitled to free eye tests.
Noise is accepted as a problem in most industries and surprisingly there
has been very little control legislation. The HSE have published a ‘Code
of Practice’ and ‘Guidance Notes’ HSG 56 for reducing the exposure of
employed persons to noise. A continuous exposure limit of below 90 dB for
an 8-hour working day is recommended by the code.
Statutory regulations and safe working procedures
11
FIGURE 1.2
Safety signs showing type of PPE to be worn.
Noise may be defined as any disagreeable or undesirable sound or sounds,
generally of a random nature, which do not have clearly defined frequencies. The usual basis for measuring noise or sound level is the decibel scale.
Whether noise of a particular level is harmful or not also depends upon
the length of exposure to it. This is the basis of the widely accepted limit of
90 dB of continuous exposure to noise for 8 hours per day.
A peak sound pressure of above 200 pascals or about 120 dB is considered
unacceptable and 130 dB is the threshold of pain for humans. If a person has
to shout to be understood at 2 m, the background noise is about 85 dB. If the
distance is only 1 m, the noise level is about 90 dB. Continuous noise at work
causes deafness, makes people irritable, affects concentration, causes
fatigue and accident proneness and may mask sounds which need to be
heard in order to work efficiently and safely.
It may be possible to engineer out some of the noise, for example, by placing a generator in a separate sound-proofed building. Alternatively, it may
be possible to provide job rotation, to rearrange work locations or provide
acoustic refuges.
Where individuals must be subjected to some noise at work it may be
reduced by ear protectors. These may be disposable ear plugs, reusable ear
plugs or ear muffs. The chosen ear protector must be suited to the user and
suitable for the type of noise and individual personnel should be trained in
its correct use.
Breathing reasonably clean air is the right of every individual, particularly at work. Some industrial processes produce dust which may present
Advanced Electrical Installation Work
a potentially serious hazard. The lung disease asbestosis is caused by the
inhalation of asbestos dust or particles and the coal dust disease pneumoconiosis, suffered by many coal miners, has made people aware of the dangers of breathing in contaminated air.
Some people may prove to be allergic to quite innocent products such as
flour dust in the food industry or wood dust in the construction industry.
The main effect of inhaling dust is a measurable impairment of lung function. This can be avoided by wearing an appropriate mask, respirator or
breathing apparatus as recommended by the company’s health and safety
policy and indicated by local safety signs.
12
A worker’s body may need protection against heat or cold, bad weather,
chemical or metal splash, impact or penetration and contaminated dust.
Alternatively, there may be a risk of the worker’s own clothes causing contamination of the product, as in the food industry. Appropriate clothing
will be recommended in the company’s health and safety policy. Ordinary
working clothes and clothing provided for food hygiene purposes are not
included in the PPE at Work Regulations.
Hands and feet may need protection from abrasion, temperature extremes,
cuts and punctures, impact or skin infection. Gloves or gauntlets provide
protection from most industrial processes but should not be worn when
operating machinery because they may become entangled in it. Care in
selecting the appropriate protective device is required; for example, barrier
creams provide only a limited protection against infection.
Boots or shoes with in-built toe caps can give protection against impact or
falling objects and, when fitted with a mild steel sole plate, can also provide
protection from sharp objects penetrating through the sole. Special slip
resistant soles can also be provided for employees working in wet areas.
Whatever the hazard to health and safety at work, the employer must be able to
demonstrate that he or she has carried out a risk analysis, made recommendations which will reduce that risk and communicated these recommendations
to the workforce. Where there is a need for PPE to protect against personal
injury and to create a safe working environment, the employer must provide
that equipment and any necessary training which might be required and the
employee must make full and proper use of such equipment and training.
RIDDOR
RIDDOR stands for Reporting of Injuries, Diseases and Dangerous
Occurrences Regulation 1995, which is sometimes referred to as RIDDOR
95, or just RIDDOR for short. The HSE requires employers to report some
work related accidents or diseases so that they can identify where and how
risks arise, investigate serious accidents and publish statistics and data to
help reduce accidents at work.
What needs reporting? Every work related death, major injury, dangerous
occurrence, disease or any injury which results in an absence from work of
over 3 days.
Statutory regulations and safe working procedures
Where an employee or member of the public is killed as a result of an accident at work the employer or his representative must report the accident to
the Environmental Health Department of the Local Authority by telephone
that day and give brief details. Within 10 days this must be followed up by a
completed accident report form (Form No. F2508). Major injuries sustained
as a result of an accident at work include amputations, loss of sight (temporary or permanent), fractures to the body other than to fingers, thumbs
or toes and any other serious injury. Once again, the Environmental Health
Department of the Local Authority must be notified by telephone on the
day that the serious injury occurs and the telephone call followed up by a
completed Form F2508 within 10 days. Dangerous occurrences are listed
in the regulations and include the collapse of a lift, an explosion or injury
caused by an explosion, the collapse of a scaffold over 5 m high, the collision of a train with any vehicle, the unintended collapse of a building and
the failure of fairground equipment.
Depending upon the seriousness of the event, it may be necessary to
immediately report the incident to the Local Authority. However, the
incident must be reported within 10 days by completing Form F2508. If
a doctor notifies an employer that an employee is suffering from a work
related disease then form F2508A must be completed and sent to the Local
Authority. Reportable diseases include certain poisonings, skin diseases,
lung disease, infections and occupational cancer. The full list is given
within the pad of report forms.
An accident at work resulting in an over 3 day injury, that is, an employee
being absent from work for over 3 days as a result of an accident at work,
requires that accident report form F2508 be sent to the Local Authority
within 10 days.
An over 3 day injury is one which is not major but results in the injured
person being away from work for more than 3 days not including the day
the injury occurred.
Who are the reports sent to? They are sent to the Environmental Health
Department of the Local Authority or the area HSE offices (see the
Appendix L of this book for area office addresses). Accident report forms
F2508 can also be obtained from them or by ringing the HSE Infoline or by
ringing the incident contact centre on telephone number 0845 300 9923.
For most businesses, a reportable accident, dangerous occurrence or disease is a very rare event. However, if a report is made, the company must
keep a record of the occurrence for 3 years after the date on which the
incident happened. The easiest way to do this would probably be to file a
photo copy of the completed accident report form F2508, but a record may
be kept in any form which is convenient.
The Control of Major Accidents and Hazards Regulations
1999
The Control of Major Accidents and Hazards (COMAH) Regulations came
into force on 1 April 1999. Their main aim is to prevent any major accidents
13
Advanced Electrical Installation Work
involving dangerous substances such as chlorine, liquefied petroleum gas
(LPG), explosives and arsenic pentoxide that would cause serious harm to
people or damage the environment. The COMAH Regulations regard risks
to the environment just as seriously as harm to people.
These regulations apply mainly to the chemical industry but also apply to
some storage facilities and nuclear sites.
Operators who fall within the scope of these regulations must ‘take all measures necessary to prevent major accidents and limit their consequences to
people and the environment’. This sets high standards of control but by
requiring operators to put in place measures for both prevention and mitigation, which means to make less serious, there is the recognition that all
risks cannot be completely eliminated. Operators must, therefore, be able
to show that they have taken ‘all measures necessary’ to prevent an accident occurring.
14
The COMAH Regulations are enforced by the HSE and the Environment
Agency.
Dangerous Substances and Explosive Atmospheres
Regulations 2002
The Dangerous Substances and Explosive Atmospheres Regulations
(DSEAR) came into force on 9 December 2002 and complement the
Management of Health and Safety at Work Regulations 1999. They are
designed to implement the safety requirements of the Chemical Agents
and Explosive Atmospheres Directive.
DSEAR deals with any dangerous substance that has the potential to create
a risk to persons from energetic or energy releasing events such as fires or
explosions. Dangerous substances include petrol, LPG, paint, solvents and
combustible or explosive dust produced in machining and sanding operations, flour mills and distilleries.
Many of these substances will also create a health risk, for example, solvents
are toxic as well as being flammable. However, DSEAR does not address
the health risk, only the fire and explosion risk. The potential health
risk is dealt with under the COSHH Regulations discussed earlier in this
chapter.
The DSEAR Regulations follow the modern risk assessment-based
approach. Technical and organizational measures are required to eliminate
or reduce risks as far as is reasonably practicable. There is a requirement to
provide equipment and procedures to deal with accidents and emergencies and also to provide information and training for employees.
So what sort of industries does DSEAR apply to? DSEAR is concerned with
the harmful effects from burns, pressure injuries from explosions and
asphyxiation arising from fires and explosions. Typical industries might be
those concerned with the storage of petrol as a fuel for vehicles, agricultural
and horticultural storage and the movement of bulk powders for the food
industry, the storing of waste dust in a range of manufacturing industries,
Statutory regulations and safe working procedures
dust produced in the mining of coal, storage and transportation of paint
and LPG.
The Construction (Design and Management) Regulations
1994
The Construction (Design and Management) Regulations (CDM) are
aimed at improving the overall management of health, safety and welfare
throughout all stages of the construction project.
Definition
‘Duty holder ’, someone who has a duty
of care for health, safety and welfare
matters on site. This phrase recognizes
the level of responsibility which electricians are expected to take on a part
of their job in order to control electrical safety in the work environment.
The person requesting that construction work commence, the client,
must first of all appoint a ‘duty holder’, someone who has a duty of care
for health, safety and welfare matters on site. This person will be called a
‘planning supervisor’. The planning supervisor must produce a ‘pre-tender’
health and safety plan and co-ordinate and manage this plan during the
early stages of construction.
The client must also appoint a principal contractor who is then required to
develop the health and safety plan made by the planning supervisor, and
keep it up to date during the construction process to completion.
The degree of detail in the health and safety plan should be in proportion
to the size of the construction project and recognize the health and safety
risks involved on that particular project. Small projects will require simple
straightforward plans, large projects, or those involving significant risk, will
require more detail. The CDM Regulations will apply to most large construction projects but they do not apply to the following:
●
●
●
●
Construction work, other than demolition work, that does not last
longer than 30 days and does not involve more than four people.
Construction work carried out inside commercial buildings such
as shops and offices, which does not interrupt the normal activities
carried out on those premises.
Construction work carried out for a domestic client.
The maintenance and removal of pipes or lagging which forms a part
of a heating or water system within the building.
The Construction (Health, Safety and Welfare)
Regulations 1996
An electrical contractor is a part of the construction team, usually as a
sub-contractor, and therefore the regulations particularly aimed at the
construction industry also influence the daily work procedures and environment of an electrician. The most important recent piece of legislation
are the Construction Regulations.
The temporary nature of construction sites makes them one of the most
dangerous places to work. These regulations are made under the Health and
Safety at Work Act 1974 and are designed specifically to promote safety at
work in the construction industry. Construction work is defined as any building or civil engineering work, including construction, assembly, alterations,
conversions, repairs, upkeep, maintenance or dismantling of a structure.
15
Advanced Electrical Installation Work
Safety First
Head protection
●
●
16
The Construction Regulations
require everyone working on a
construction site to wear head
protection
This includes electricians.
The general provision sets out minimum standards to promote a good level
of safety on site. Schedules specify the requirements for guardrails, working platforms, ladders, emergency procedures, lighting and welfare facilities. Welfare facilities set out minimum provisions for site accommodation:
washing facilities, sanitary conveniences and protective clothing. There is
now a duty for all those working on construction sites to wear head protection, and this includes electricians working on site as sub-contractors.
Building Regulations – Part P 2006
The Building Regulations lay down the design and build standards for construction work in buildings in a series of Approved Documents. The scope
of each Approved Document is given below:
Part A
Part B
Part C
Part D
Part E
Part F
Part G
Part H
Part J
Part K
Part L
Part M
Part N
Part P
structure
fire safety
site preparation and resistance to moisture
toxic substances
resistance to the passage of sound
ventilation
hygiene
drainage and waste disposal
combustion appliances and fuel storage systems
protection from falling, collision and impact
conservation of fuel and power
access and facilities for disabled people
glazing – safety in relation to impact, opening and cleaning
electrical safety.
Part P of the Building Regulations was published on 22 July 2004, bringing domestic electrical installations in England and Wales under building
regulations control. This means that anyone carrying out domestic electrical installation work from 1 January 2005 must comply with Part P of
the Building Regulations. An ammended document was published in an
attempt at greater clarity and this came into effect on 6 April 2006.
If the electrical installation meets the requirements of the IEE Regulations
BS 7671, then it will also meet the requirements of Part P of the Building
Regulations, so no change there. What is going to change under Part P is
this new concept of ‘notification’ to carry out electrical work.
NOTIFIABLE ELECTRICAL WORK
Any work to be undertaken by a firm or individual who is not registered
under an ‘approved competent person scheme’ must be notified to the
Local Authority Building Control Body before work commences. That is,
work that involves:
●
the provision of at least one new circuit,
●
work carried out in kitchens,
Statutory regulations and safe working procedures
●
●
work carried out in bathrooms,
work carried out in special locations such as swimming pools and
hot air saunas.
Upon completion of the work, the Local Authority Building Control Body
will test and inspect the electrical work for compliance with Part P of the
Building Regulations.
NON-NOTIFIABLE ELECTRICAL WORK
Work carried out by a person or firm registered under an authorized
Competent Persons Self-Certification Scheme or electrical installation
work that does not include the provision of a new circuit. This includes
work such as:
●
●
●
●
●
●
replacing accessories such as socket outlets, control switches and
ceiling roses;
replacing a like for like cable for a single circuit which has become
damaged by, for example, impact, fire or rodent;
re-fixing or replacing the enclosure of an existing installation component provided the circuits protective measures are unaffected;
providing mechanical protection to existing fixed installations;
adding lighting points (light fittings and switches) to an existing circuit,
provided that the work is not in a kitchen, bathroom or special location;
installing or upgrading the main or supplementary equipotential
bonding provided that the work is not in a kitchen, bathroom or special location.
All replacement work is non-notifiable even when carried out in kitchens,
bathrooms and special locations, but certain work carried out in kitchens,
bathrooms and special locations may be notifiable, even when carried
out by an authorized competent person. The IEE have published a guide
called the Electricians’ Guide to the Building Regulations which brings clarity to this subject. In specific cases the Local Authority Building Control
Officer or an approved Inspector will be able to confirm whether Building
Regulations apply.
Failure to comply with the Building Regulations is a criminal offence and
Local Authorities have the power to require the removal or alteration of
work that does not comply with these requirements.
Electrical work carried out by DIY home-owners will still be permitted after
the introduction of Part P. Those carrying out notifiable DIY work must first
submit a building notice to the Local Authority before the work begins.
The work must then be carried out to the standards set by the IEE Wiring
Regulations BS 7671 and a building control fee paid for such work to be
inspected and tested by the Local Authority.
17
Advanced Electrical Installation Work
COMPETENT PERSONS SCHEME
The Competent Persons Self-Certification Scheme is aimed at those who
carry out electrical installation work as the primary activity of their business. The government has approved schemes to be operated by BRE
Certification Ltd., British Standards Institution, ELECSA Ltd., NICEIC
Certification Services Ltd., and Napit Certification Services Ltd. All the
different bodies will operate the scheme to the same criteria and will be
monitored by the Department for Communities and Local Government,
formally called the Office of the Deputy Prime Minister.
Those individuals or firms wishing to join the Competent Persons Scheme
will need to demonstrate their competence, if necessary, by first undergoing training. The work of members will then be inspected at least once
each year. There will be an initial registration and assessment fee and then
an annual membership and inspection fee.
18
The Electricity Safety, Quality and Continuity
Regulations 2002
The Electricity Safety, Quality and Continuity Regulations replaces the
Electricity Supply Regulations 1988. They are statutory regulations
which are enforceable by the laws of the land. They are designed to
ensure a proper and safe supply of electrical energy up to the consumer’s
terminals.
These regulations impose requirements upon the regional electricity
companies regarding the installation and use of electric lines and equipment. The regulations are administered by the Engineering Inspectorate
of the Electricity Division of the Department of Energy and will not normally concern the electrical contractor except that it is these regulations
which lay down the earthing requirement of the electrical supply at the
meter position.
The regional electricity companies must declare the supply voltage and
maintain its value between prescribed limits or tolerances.
The government agreed on 1 January 1995 that the electricity supplies in
the United Kingdom would be harmonized with those of the rest of Europe.
Thus the voltages used previously in low voltage supply systems of 415 and
240 V have become 400 V for three-phase supplies and 230 V for singlephase supplies. The permitted tolerances to the nominal voltage have also
been changed from ⫾6% to ⫹10% and ⫺6%.
The next proposed change is for the tolerance levels to be adjusted to
⫾10% of the declared nominal voltage. (IEE Regulations Appendix 2:14).
The frequency is maintained at an average value of 50 Hz over 24 hours so
that electric clocks remain accurate.
Regulation 29 gives the area boards the power to refuse to connect a supply to an installation which in their opinion is not constructed, installed
and protected to an appropriately high standard. This regulation would
Statutory regulations and safe working procedures
only be enforced if the installation did not meet the requirements of the
IEE Regulations for Electrical Installations.
The Electricity at Work Regulations 1989
This legislation came into force in 1990 and replaced earlier regulations
such as the Electricity (Factories Act) Special Regulations 1944. The regulations are made under the Health and Safety at Work Act 1974, and enforced
by the HSE. The purpose of the regulations is to ‘require precautions to be
taken against the risk of death or personal injury from electricity in work
activities’.
Section 4 of the Electricity at Work Regulations (EWR) tells us that ‘all
systems must be constructed so as to prevent danger …, and be properly maintained. … Every work activity shall be carried out in a manner
which does not give rise to danger. … In the case of work of an electrical
nature, it is preferable that the conductors be made dead before work
commences’.
The EWR do not tell us specifically how to carry out our work activities and
ensure compliance, but if proceedings were brought against an individual
for breaking the EWR, the only acceptable defence would be ‘to prove that
all reasonable steps were taken and all diligence exercised to avoid the
offence’ (Regulation 29).
An electrical contractor could reasonably be expected to have ‘exercised
all diligence’ if the installation was wired according to the IEE Wiring
Regulations and this is confirmed in the 17th Edition at Regulation 114 (see
below). However, electrical contractors must become more ‘legally aware’
following the conviction of an electrician for manslaughter at Maidstone
Crown Court in 1989. The Court accepted that an electrician had caused
the death of another man as a result of his shoddy work in wiring up a central heating system. He received a 9 month suspended prison sentence.
This case has set an important legal precedent, and in future any tradesman or professional who causes death through negligence or poor workmanship risks prosecution and possible imprisonment.
DUTY OF CARE
Definition
Everyone has a duty of care but not
everyone is a duty holder. The person
who exercises ‘control over the whole
systems, equipment and conductors’
and is the Electrical Company’s representative on site, is the duty holder.
The Health and Safety at Work Act and the Electricity at Work Regulations
(EWR) make numerous references to employer and employees having a ‘duty
of care’ for the health and safety of others in the work environment. In this
context the EWR refer to a person as a ‘duty holder’. This phrase recognizes
the level of responsibility which electricians are expected to take on a part of
their job in order to control electrical safety in the work environment.
Everyone has a duty of care but not everyone is a duty holder. The regulations recognize the amount of control that an individual might exercise over
the whole
To Joyce, Samantha and Victoria
Advanced Electrical
Installation Work
FIFTH EDITION
TREVOR LINSLEY
Senior Lecturer
Blackpool and The Fylde College
AMSTERDAM • BOSTON • HEIDELBERG • LONDON • NEW YORK • OXFORD
PARIS • SAN DIEGO • SAN FRANCISCO • SINGAPORE • SYDNEY • TOKYO
Newnes is an imprint of Elsevier
Newnes
An imprint of Elsevier
Linacre House, Jordan Hill, Oxford OX2 8DP
30 Corporate Drive, Burlington, MA 01803
First published by Arnold 1998
Reprinted by Butterworth-Heinemann 2001, 2002, 2003 (twice), 2004 (twice)
Fourth edition 2005
Fifth edition 2008
Copyright © 2008, Trevor Linsley. Published by Elsevier Ltd. All rights reserved
The right of Trevor Linsley to be identified as the author of this work has been asserted in accordance with the
Copyright, Designs and Patents Act 1988
No part of this publication may be reproduced in any material form (including photocopying or storing in any medium by electronic
means and whether or not transiently or incidentally to some other use of this publication) without the written permission of the
copyright holder except in accordance with the provisions of the Copyright, Designs and Patents Act 1988 or under the terms of a
licence issued by the Copyright Licensing Agency Ltd, 90 Tottenham Court Road, London, England W1T 4LP. Applications for the
copyright holder’s written permission to reproduce any part of this publication should be addressed to the publisher.
Permissions may be sought directly from Elsevier’s Science and Technology Rights Department in Oxford, UK;
phone: (⫹44) (0) 1865 843830; fax: (⫹44) (0) 1865 853333; e-mail: [email protected]. You may also complete
your request on-line via the Elsevier homepage (http://www.elsevier.com), by selecting ‘Customer Support’ and then ‘Obtaining Permissions’.
Whilst the advice and information in this book is believed to be true and accurate at the date of going to press, neither the
author nor the publisher can accept any legal responsibility or liability for any errors or omissions that may be made.
British Library Cataloguing in Publication Data
A catalogue record for this book is available from the British Library
For information on all Newnes publications
visit our website at www.newnespress.com
ISBN 978-0-7506-8752-2
Typeset by Charon Tec Ltd., A Macmillan Company (www.macmillansolutions.com)
Printed and bound in Great Britain
Contents
Preface
vii
Acknowledgements
ix
UNIT 1 – Application of health and safety and electrical principles
1
Chapter 1 Statutory regulations and safe working procedures
3
Chapter 2 Safe working practices and emergency procedures
51
Chapter 3 Effective working practices
77
Chapter 4 Electrical systems and components
95
Chapter 5 Electricity supply systems, protection and earthing
181
Chapter 6 Electrical machines and motors
227
UNIT 2 – Installation (buildings and structures): inspection, testing and commissioning
251
Chapter 7 Safe, effective and efficient working practices
253
Chapter 8 Inspection, testing and commissioning
311
UNIT 3 – Installation (buildings and structures): fault diagnosis and rectification
347
Chapter 9 Fault diagnosis and repair
349
Chapter 10 Restoring systems to working order
373
Answers to Check your understanding
381
Appendix A: Obtaining information and electronic components
383
Appendix B: Abbreviations, symbols and codes
385
Glossary of terms
387
Index
397
v
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Preface
The 5th Edition of Advanced Electrical Installation Work has been completely rewritten in 10 Chapters to closely match the 10 Outcomes of the
City and Guilds qualification. The technical content has been revised and
updated to the requirements of the new 17th Edition of the IEE Regulations
BS 7671: 2008. Improved page design with new illustrations gives greater
clarity to each topic.
This book of electrical installation theory and practice will be of value to
the electrical trainee working towards:
●
●
●
●
The City and Guilds 2330 Level 3 Certificate in Electrotechnical
Technology, Installation Route.
The City and Guilds 2356 Level 2 NVQ in Installing Electrotechnical
Systems.
The SCOTVEC and BTEC Electrical Utilisation Units at Levels II and
III.
Those taking Engineering NVQ and modern Apprenticeship
Courses.
Advanced Electrical Installation Work provides a sound basic knowledge of
electrical practice which other trades in the construction industry will find
of value, particularly those involved in multi-skilling activities.
The book incorporates the requirements of the latest Regulations,
particularly:
●
17th Edition IEE Wiring Regulations.
●
British Standards BS 7671: 2008.
●
Part P of the Building Regulations, Electrical Safety in Dwellings:
2006.
●
Hazardous Waste Regulations: 2005.
●
Work at Height Regulations: 2005.
Trevor Linsley
2008
vii
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Acknowledgements
I would like to acknowledge the assistance given by the following manufacturers and professional organizations in the preparation of this book:
●
●
The Institution of Engineering and Technology for permission
to reproduce Regulations and Tables from the 17th Edition IEE
Regulations.
The British Standards Institution for permission to reproduce material from BS 7671: 2008.
●
Crabtree Electrical Industries for technical information and data.
●
RS Components Limited for technical information and photographs.
●
Stocksigns Limited for technical information and photographs.
●
●
Wylex Electrical Components for technical information and
photographs.
Jason vann Smith MIET MiEEE MBCS MACM for the photographs
used in the page design.
I would like to thank the many College Lecturers who responded to the
questionnaire from Elsevier the publishers, regarding the proposed new
edition of this book. Their recommendations have been taken into account
in producing this improved 5th Edition.
I would also like to thank the editorial and production staff at Elsevier the
publishers for their enthusiasm and support. They were able to publish
this 5th Edition within the very short timescale created by the publication
of the 17th Edition of the IEE Regulations.
Finally I would like to thank Joyce, Samantha and Victoria for their support
and encouragement.
ix
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This page intentionally left blank
Ch 1
Statutory regulations and
safe working procedures
3
U
V
W
Unit 1 - Application of health and safety and electrical principles – Outcome 1
Underpinning knowledge: when you have completed this chapter you should be able to:
●
●
●
6
identify the Safety Regulations relevant to the electrotechnical industry
6
6
identify environmental legislation relevant to the electrotechnical industry
C1
state employer and employee responsibilities
●
state the human and environmental conditions leading to workplace accidents
●
describe a procedure for reporting accidents
●
recognize workplace safety signs
●
carry out a risk assessment
●
list the changing work patterns within the industry
2
L1
2
L2
2
L3
To 3 phase supply
C1
2
C3
4
5
6
Advanced Electrical Installation Work
Introduction
This first chapter of Advanced Electrical Installation work covers the health
and safety core skills required by the City and Guilds Level 3 Certificate
in Electrotechnical Technology. That is the Health and Safety Laws and
Regulations that underpin the electrotechnical industry.
Let me begin by looking at the background to the modern Health and
Safety Regulations and the electricity supply and wiring regulations.
Electricity generation as we know it today began when Michael Faraday
conducted the famous ring experiment in 1831. This experiment, together
with many other experiments of the time, made it possible for Lord Kelvin
and Sebastian de Ferranti to patent in 1882 the designs for an electrical
machine called the Ferranti–Thompson dynamo, which enabled the generation of electricity on a commercial scale.
4
In 1887 the London electric supply corporation was formed with Ferranti
as chief engineer. This was one of the many privately owned electricity
generating stations supplying the electrical needs of the United Kingdom.
As the demand for electricity grew, more privately owned generating stations were built until eventually the government realized that electricity
was a national asset which would benefit from nationalization.
In 1926 the Electricity Supply Act placed the responsibility for generation in
the hands of the Central Electricity Board. In England and Wales the Central
Electricity Generating Board (CEGB) had the responsibility for the generation
and transmission of electricity on the supergrid. In Scotland, generation was
the joint responsibility of the North of Scotland Hydro-Electricity Board and
the South of Scotland Electricity Board. In Northern Ireland electricity generation was the responsibility of the Northern Ireland Electricity Service.
In 1988 Cecil Parkinson, the Secretary of State for Energy in the Conservative
government, proposed the denationalization of the electricity supply industry; this became law in March 1991, thereby returning the responsibility
for generation, transmission and distribution to the private sector. It was
anticipated that this action, together with new legislation over the security
of supplies, would lead to a guaranteed quality of provision, with increased
competition leading eventually to cheaper electricity.
During the period of development of the electricity services, particularly in
the early days, poor design and installation led to many buildings being damaged by fire and the electrocution of human beings and livestock. It was the
insurance companies which originally drew up a set of rules and guidelines
of good practice in the interest of reducing the number of claims made upon
them. The first rules were made by the American Board of Fire Underwriters
and were quickly followed by the Phoenix Rules of 1882. In the same year the
first edition of the Rules and Regulations for the Prevention of Fire Risk arising from Electrical Lighting was issued by the Institute of Electrical Engineers.
The current edition of these regulations is called the Requirements for
Electrical Installations, IEE Wiring Regulations (BS 7671: 2008), and since
Statutory regulations and safe working procedures
July 2008 we have been using the 17th edition. All the rules have been
revised, updated and amended at regular intervals to take account of modern developments, and the 17th edition brought the UK Regulations into
harmony with those of the rest of Europe.
The laws and regulations affecting the electrotechnical industry have
steadily increased over the years. There is a huge amount of legislation
from the European law-makers in Brussels. These laws and regulations
will permeate each and every sector of the electrotechnical industry and
reform and modify our future work patterns and behaviour.
In this section I want to deal with the laws and regulations that affect our
industry under three general headings because there are a large number of
them, and it may help us to appreciate the reasons for them.
(i) First of all I want to look at the laws concerned with health and
safety at work, making the working environment safe.
(ii) Then I want to go on to the laws that protect our environment
from, for example, industrial waste and pollution.
(iii) Finally, I will look at employment legislation and the laws which
protect us as individual workers, people and citizens in Chapter 3
of this book.
The Health and Safety at Work Act 1974
Many governments have passed laws aimed at improving safety at work but
the most important recent legislation has been the Health and Safety at Work
Act 1974. The purpose of the act is to provide the legal framework for stimulating and encouraging high standards of health and safety at work; the act
puts the responsibility for safety at work on both workers and managers.
The Health and Safety at Work Act is an ‘Enabling Act’ that allows the
Secretary of State to make further laws, known as regulations, without
the need to pass another Act of Parliament. Regulations are law, passed
by Parliament and are usually made under the Health and Safety at
Work Act 1974. This applies to regulations based on European directives
as well as new UK Regulations. The way it works is that the Health and
Safety at Work Act established the Health and Safety Commission (HSC)
and gave it the responsibility of drafting new regulations and enforcing
them through its executive arm known as the Health and Safety Executive
(HSE) or through the local Environmental Health Officers (EHO). The
HSC has equal representation from employers, trade unions and special interest groups. Their role is to set out the regulations as goals to be
achieved. They describe what must be achieved in the interests of safety,
but not how it must be done.
Definition
Under the Health and Safety at Work Act an employer has a duty to care for
Under the Health and Safety at Work the health and safety of employees (Section 2 of the Act). To do this he has
Act an employer has a duty to care for a responsibility to ensure that:
the health and safety of employees.
●
the working conditions and standard of hygiene are appropriate;
5
Advanced Electrical Installation Work
Safety First
●
the plant, tools and equipment are properly maintained;
●
safe systems of work are in place;
Laws
The Health and Safety at Work Act
provides the legal framework for stimulating and encouraging health and
safety at work. It is:
●
the most important,
●
the most far reaching,
●
single piece of legislation.
●
safe methods of handling, storing and transporting goods and materials are used;
●
there is a system for reporting accidents in the workplace;
●
the company has a written Health & Safety Policy statement;
●
Definition
●
the necessary safety equipment – such as personal protective equipment (PPE), dust and fume extractors and machine guards – are
available and properly used;
the workers are trained to use equipment and plant safely.
Employees have a duty to care for
their own health and safety and that Employees have a duty to care for their own health and safety and that of
of others who may be afected by others who may be affected by their actions (Section 7 of the Act). To do
their actions.
this they must:
6
●
●
●
take reasonable care to avoid injury to themselves or others as a
result of their work activity;
co-operate with their employer, helping him or her to comply with
the requirements of the act;
not interfere with or misuse anything provided to protect their
health and safety.
Failure to comply with the Health and Safety at Work Act is a criminal
offence and any infringement of the law can result in heavy fines, a prison
sentence or both.
ENFORCEMENT
Laws and rules must be enforced if they are to be effective. The system
of control under the Health and Safety at Work Act comes from the HSE
which is charged with enforcing the law. The HSE is divided into a number of specialist inspectorates or sections which operate from local offices
throughout the United Kingdom. From the local offices the inspectors visit
individual places of work.
The HSE inspectors have been given wide-ranging powers to assist them in
the enforcement of the law. They can:
1. enter premises unannounced and carry out investigations, take
measurements or photographs;
2. take statements from individuals;
3. check the records and documents required by legislation;
4. give information and advice to an employee or employer about
safety in the workplace;
5. demand the dismantling or destruction of any equipment, material
or substance likely to cause immediate serious injury;
Statutory regulations and safe working procedures
6. issue an improvement notice which will require an employer to put
right, within a specified period of time, a minor infringement of the
legislation;
7. issue a prohibition notice which will require an employer to stop
immediately any activity likely to result in serious injury, and which
will be enforced until the situation is corrected;
8. prosecute all persons who fail to comply with their safety duties,
including employers, employees, designers, manufacturers, suppliers
and the self-employed.
SAFETY DOCUMENTATION
Under the Health and Safety at Work Act, the employer is responsible for
ensuring that adequate instruction and information is given to employees to make them safety-conscious. Part 1, Section 3 of the Act instructs all
employers to prepare a written health and safety policy statement and to
bring this to the notice of all employees. Your employer must let you know
who your safety representatives are and the new health and safety poster
shown in Fig. 1.1 has a blank section into which the names and contact
information of your specific representatives can be added. This is a large
laminated poster, 595 ⫻ 415 mm suitable for wall or notice board display.
FIGURE 1.1
New Health and Safety Law poster. Source: HSE © Crown copyright material is reproduced with the
permission of the Controller of HMSO and Her Majesty’s Stationery Office, Norwich.
7
Advanced Electrical Installation Work
All workplaces employing five or more people must display the type of
poster shown in Fig. 1.1 after 30 June 2000.
Safety First
Information
●
Have you seen the new Health
and Safety Law poster like Fig 1.1?
– in your place of work
8
– at the college.
●
Were the blank sections illed in?
To promote adequate health and safety measures the employer must
consult with the employees’ safety representatives. In companies which
employ more than 20 people this is normally undertaken by forming a
safety committee which is made up of a safety officer and employee representatives, usually nominated by a trade union. The safety officer is
usually employed full-time in that role. Small companies might employ
a safety supervisor, who will have other duties within the company, or
alternatively they could join a ‘safety group’. The safety group then shares
the cost of employing a safety adviser or safety officer, who visits each
company in rotation. An employee who identifies a dangerous situation
should initially report to his site safety representative. The safety representative should then bring the dangerous situation to the notice of
the safety committee for action which will remove the danger. This may
mean changing company policy or procedures or making modifications
to equipment. All actions of the safety committee should be documented
and recorded as evidence that the company takes seriously its health and
safety policy.
The Management of Health and Safety at Work
Regulations 1999
The Health and Safety at Work Act 1974 places responsibilities on employers to have robust Health and Safety systems and procedures in the workplace. Directors and managers of any company who employ more than
five employees can be held personally responsible for failures to control
health and safety.
The Management of Health and Safety at Work Regulations 1999 tell us that
employers must systematically examine the workplace, the work activity
and the management of safety in the establishment through a process of
‘risk assessments’. A record of all significant risk assessment findings must
be kept in a safe place and be available to an HSE inspector if required.
Information based on these findings must be communicated to relevant
staff and if changes in work behaviour patterns are recommended in the
interests of safety, then they must be put in place. The process of risk
assessment is considered in detail later in this chapter.
Risks, which may require a formal assessment in the electrotechnical
industry, might be:
●
working at heights;
●
using electrical power tools;
●
falling objects;
●
working in confined places;
●
electrocution and personal injury;
Statutory regulations and safe working procedures
●
working with ‘live’ equipment;
●
using hire equipment;
●
manual handling: pushing, pulling, lifting;
●
site conditions: falling objects, dust, weather, water, accidents and
injuries.
And any other risks which are particular to a specific type of work place or
work activity.
Provision and Use of Work Equipment Regulations 1998
These regulations tidy up a number of existing requirements already in place
under other regulations such as the Health and Safety at Work Act 1974, the
Factories Act 1961 and the Offices, Shops and Railway Premises Act 1963.
The Provision and Use of Work Equipment Regulations 1998 places a general
duty on employers to ensure minimum requirements of plant and equipment. If an employer has purchased good quality plant and equipment,
which is well maintained, there is little else to do. Some older equipment may
require modifications to bring it in line with modern standards of dust extraction, fume extraction or noise, but no assessments are required by the regulations other than those generally required by the Management Regulations
1999 discussed previously.
The Control of Substances Hazardous to Health
Regulations 2002
The original Control of Substances Hazardous to Health (COSHH)
Regulations were published in 1988 and came into force in October 1989.
They were re-enacted in 1994 with modifications and improvements, and
the latest modifications and additions came into force in 2002.
The COSHH Regulations control people’s exposure to hazardous substances in the workplace. Regulation 6 requires employers to assess the
risks to health from working with hazardous substances, to train employees
in techniques which will reduce the risk and provide PPE so that employees will not endanger themselves or others through exposure to hazardous
substances. Employees should also know what cleaning, storage and disposal procedures are required and what emergency procedures to follow.
The necessary information must be available to anyone using hazardous
substances as well as to visiting HSE inspectors.
Hazardous substances include:
1. any substance which gives off fumes causing headaches or respiratory irritation;
2. man-made fibres which might cause skin or eye irritation (e.g. loft
insulation);
3. acids causing skin burns and breathing irritation (e.g. car batteries,
which contain dilute sulphuric acid);
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Advanced Electrical Installation Work
4. solvents causing skin and respiratory irritation (strong solvents are
used to cement together PVC conduit fittings and tube);
5. fumes and gases causing asphyxiation (burning PVC gives off toxic
fumes);
6. cement and wood dust causing breathing problems and eye
irritation;
7. exposure to asbestos – although the supply and use of the most hazardous asbestos material is now prohibited, huge amounts were
installed between 1950 and 1980 in the construction industry and
much of it is still in place today. In their latest amendments the
COSHH Regulations focus on giving advice and guidance to builders and contractors on the safe use and control of asbestos products.
These can be found in Guidance Notes EH 71.
Where PPE is provided by an employer, employees have a duty to use it to
safeguard themselves.
10
PPE at Work Regulations 1992
PPE is defined as all equipment designed to be worn, or held, to protect
against a risk to health and safety. This includes most types of protective
clothing, and equipment such as eye, foot and head protection, safety harnesses, life jackets and high-visibility clothing.
Under the Health and Safety at Work Act, employers must provide free of
charge any PPE and employees must make full and proper use of it. Safety
signs such as those shown in Fig. 1.2 are useful reminders of the type
of PPE to be used in a particular area. The vulnerable parts of the body
which may need protection are the head, eyes, ears, lungs, torso, hands
and feet and, additionally, protection from falls may need to be considered. Objects falling from a height present the major hazard against which
head protection is provided. Other hazards include striking the head
against projections and hair becoming entangled in machinery. Typical
methods of protection include helmets, light duty scalp protectors called
‘bump caps’ and hairnets.
Safety First
PPE
●
●
What type of PPE do you use at
work?
Make a list in the margin of the
book.
The eyes are very vulnerable to liquid splashes, flying particles and light
emissions such as ultraviolet light, electric arcs and lasers. Types of eye
protectors include safety spectacles, safety goggles and face shields. Screen
based workstations are being used increasingly in industrial and commercial locations by all types of personnel. Working with VDUs (visual display
units) can cause eye strain and fatigue and, therefore, work patterns should
be varied and operators are entitled to free eye tests.
Noise is accepted as a problem in most industries and surprisingly there
has been very little control legislation. The HSE have published a ‘Code
of Practice’ and ‘Guidance Notes’ HSG 56 for reducing the exposure of
employed persons to noise. A continuous exposure limit of below 90 dB for
an 8-hour working day is recommended by the code.
Statutory regulations and safe working procedures
11
FIGURE 1.2
Safety signs showing type of PPE to be worn.
Noise may be defined as any disagreeable or undesirable sound or sounds,
generally of a random nature, which do not have clearly defined frequencies. The usual basis for measuring noise or sound level is the decibel scale.
Whether noise of a particular level is harmful or not also depends upon
the length of exposure to it. This is the basis of the widely accepted limit of
90 dB of continuous exposure to noise for 8 hours per day.
A peak sound pressure of above 200 pascals or about 120 dB is considered
unacceptable and 130 dB is the threshold of pain for humans. If a person has
to shout to be understood at 2 m, the background noise is about 85 dB. If the
distance is only 1 m, the noise level is about 90 dB. Continuous noise at work
causes deafness, makes people irritable, affects concentration, causes
fatigue and accident proneness and may mask sounds which need to be
heard in order to work efficiently and safely.
It may be possible to engineer out some of the noise, for example, by placing a generator in a separate sound-proofed building. Alternatively, it may
be possible to provide job rotation, to rearrange work locations or provide
acoustic refuges.
Where individuals must be subjected to some noise at work it may be
reduced by ear protectors. These may be disposable ear plugs, reusable ear
plugs or ear muffs. The chosen ear protector must be suited to the user and
suitable for the type of noise and individual personnel should be trained in
its correct use.
Breathing reasonably clean air is the right of every individual, particularly at work. Some industrial processes produce dust which may present
Advanced Electrical Installation Work
a potentially serious hazard. The lung disease asbestosis is caused by the
inhalation of asbestos dust or particles and the coal dust disease pneumoconiosis, suffered by many coal miners, has made people aware of the dangers of breathing in contaminated air.
Some people may prove to be allergic to quite innocent products such as
flour dust in the food industry or wood dust in the construction industry.
The main effect of inhaling dust is a measurable impairment of lung function. This can be avoided by wearing an appropriate mask, respirator or
breathing apparatus as recommended by the company’s health and safety
policy and indicated by local safety signs.
12
A worker’s body may need protection against heat or cold, bad weather,
chemical or metal splash, impact or penetration and contaminated dust.
Alternatively, there may be a risk of the worker’s own clothes causing contamination of the product, as in the food industry. Appropriate clothing
will be recommended in the company’s health and safety policy. Ordinary
working clothes and clothing provided for food hygiene purposes are not
included in the PPE at Work Regulations.
Hands and feet may need protection from abrasion, temperature extremes,
cuts and punctures, impact or skin infection. Gloves or gauntlets provide
protection from most industrial processes but should not be worn when
operating machinery because they may become entangled in it. Care in
selecting the appropriate protective device is required; for example, barrier
creams provide only a limited protection against infection.
Boots or shoes with in-built toe caps can give protection against impact or
falling objects and, when fitted with a mild steel sole plate, can also provide
protection from sharp objects penetrating through the sole. Special slip
resistant soles can also be provided for employees working in wet areas.
Whatever the hazard to health and safety at work, the employer must be able to
demonstrate that he or she has carried out a risk analysis, made recommendations which will reduce that risk and communicated these recommendations
to the workforce. Where there is a need for PPE to protect against personal
injury and to create a safe working environment, the employer must provide
that equipment and any necessary training which might be required and the
employee must make full and proper use of such equipment and training.
RIDDOR
RIDDOR stands for Reporting of Injuries, Diseases and Dangerous
Occurrences Regulation 1995, which is sometimes referred to as RIDDOR
95, or just RIDDOR for short. The HSE requires employers to report some
work related accidents or diseases so that they can identify where and how
risks arise, investigate serious accidents and publish statistics and data to
help reduce accidents at work.
What needs reporting? Every work related death, major injury, dangerous
occurrence, disease or any injury which results in an absence from work of
over 3 days.
Statutory regulations and safe working procedures
Where an employee or member of the public is killed as a result of an accident at work the employer or his representative must report the accident to
the Environmental Health Department of the Local Authority by telephone
that day and give brief details. Within 10 days this must be followed up by a
completed accident report form (Form No. F2508). Major injuries sustained
as a result of an accident at work include amputations, loss of sight (temporary or permanent), fractures to the body other than to fingers, thumbs
or toes and any other serious injury. Once again, the Environmental Health
Department of the Local Authority must be notified by telephone on the
day that the serious injury occurs and the telephone call followed up by a
completed Form F2508 within 10 days. Dangerous occurrences are listed
in the regulations and include the collapse of a lift, an explosion or injury
caused by an explosion, the collapse of a scaffold over 5 m high, the collision of a train with any vehicle, the unintended collapse of a building and
the failure of fairground equipment.
Depending upon the seriousness of the event, it may be necessary to
immediately report the incident to the Local Authority. However, the
incident must be reported within 10 days by completing Form F2508. If
a doctor notifies an employer that an employee is suffering from a work
related disease then form F2508A must be completed and sent to the Local
Authority. Reportable diseases include certain poisonings, skin diseases,
lung disease, infections and occupational cancer. The full list is given
within the pad of report forms.
An accident at work resulting in an over 3 day injury, that is, an employee
being absent from work for over 3 days as a result of an accident at work,
requires that accident report form F2508 be sent to the Local Authority
within 10 days.
An over 3 day injury is one which is not major but results in the injured
person being away from work for more than 3 days not including the day
the injury occurred.
Who are the reports sent to? They are sent to the Environmental Health
Department of the Local Authority or the area HSE offices (see the
Appendix L of this book for area office addresses). Accident report forms
F2508 can also be obtained from them or by ringing the HSE Infoline or by
ringing the incident contact centre on telephone number 0845 300 9923.
For most businesses, a reportable accident, dangerous occurrence or disease is a very rare event. However, if a report is made, the company must
keep a record of the occurrence for 3 years after the date on which the
incident happened. The easiest way to do this would probably be to file a
photo copy of the completed accident report form F2508, but a record may
be kept in any form which is convenient.
The Control of Major Accidents and Hazards Regulations
1999
The Control of Major Accidents and Hazards (COMAH) Regulations came
into force on 1 April 1999. Their main aim is to prevent any major accidents
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Advanced Electrical Installation Work
involving dangerous substances such as chlorine, liquefied petroleum gas
(LPG), explosives and arsenic pentoxide that would cause serious harm to
people or damage the environment. The COMAH Regulations regard risks
to the environment just as seriously as harm to people.
These regulations apply mainly to the chemical industry but also apply to
some storage facilities and nuclear sites.
Operators who fall within the scope of these regulations must ‘take all measures necessary to prevent major accidents and limit their consequences to
people and the environment’. This sets high standards of control but by
requiring operators to put in place measures for both prevention and mitigation, which means to make less serious, there is the recognition that all
risks cannot be completely eliminated. Operators must, therefore, be able
to show that they have taken ‘all measures necessary’ to prevent an accident occurring.
14
The COMAH Regulations are enforced by the HSE and the Environment
Agency.
Dangerous Substances and Explosive Atmospheres
Regulations 2002
The Dangerous Substances and Explosive Atmospheres Regulations
(DSEAR) came into force on 9 December 2002 and complement the
Management of Health and Safety at Work Regulations 1999. They are
designed to implement the safety requirements of the Chemical Agents
and Explosive Atmospheres Directive.
DSEAR deals with any dangerous substance that has the potential to create
a risk to persons from energetic or energy releasing events such as fires or
explosions. Dangerous substances include petrol, LPG, paint, solvents and
combustible or explosive dust produced in machining and sanding operations, flour mills and distilleries.
Many of these substances will also create a health risk, for example, solvents
are toxic as well as being flammable. However, DSEAR does not address
the health risk, only the fire and explosion risk. The potential health
risk is dealt with under the COSHH Regulations discussed earlier in this
chapter.
The DSEAR Regulations follow the modern risk assessment-based
approach. Technical and organizational measures are required to eliminate
or reduce risks as far as is reasonably practicable. There is a requirement to
provide equipment and procedures to deal with accidents and emergencies and also to provide information and training for employees.
So what sort of industries does DSEAR apply to? DSEAR is concerned with
the harmful effects from burns, pressure injuries from explosions and
asphyxiation arising from fires and explosions. Typical industries might be
those concerned with the storage of petrol as a fuel for vehicles, agricultural
and horticultural storage and the movement of bulk powders for the food
industry, the storing of waste dust in a range of manufacturing industries,
Statutory regulations and safe working procedures
dust produced in the mining of coal, storage and transportation of paint
and LPG.
The Construction (Design and Management) Regulations
1994
The Construction (Design and Management) Regulations (CDM) are
aimed at improving the overall management of health, safety and welfare
throughout all stages of the construction project.
Definition
‘Duty holder ’, someone who has a duty
of care for health, safety and welfare
matters on site. This phrase recognizes
the level of responsibility which electricians are expected to take on a part
of their job in order to control electrical safety in the work environment.
The person requesting that construction work commence, the client,
must first of all appoint a ‘duty holder’, someone who has a duty of care
for health, safety and welfare matters on site. This person will be called a
‘planning supervisor’. The planning supervisor must produce a ‘pre-tender’
health and safety plan and co-ordinate and manage this plan during the
early stages of construction.
The client must also appoint a principal contractor who is then required to
develop the health and safety plan made by the planning supervisor, and
keep it up to date during the construction process to completion.
The degree of detail in the health and safety plan should be in proportion
to the size of the construction project and recognize the health and safety
risks involved on that particular project. Small projects will require simple
straightforward plans, large projects, or those involving significant risk, will
require more detail. The CDM Regulations will apply to most large construction projects but they do not apply to the following:
●
●
●
●
Construction work, other than demolition work, that does not last
longer than 30 days and does not involve more than four people.
Construction work carried out inside commercial buildings such
as shops and offices, which does not interrupt the normal activities
carried out on those premises.
Construction work carried out for a domestic client.
The maintenance and removal of pipes or lagging which forms a part
of a heating or water system within the building.
The Construction (Health, Safety and Welfare)
Regulations 1996
An electrical contractor is a part of the construction team, usually as a
sub-contractor, and therefore the regulations particularly aimed at the
construction industry also influence the daily work procedures and environment of an electrician. The most important recent piece of legislation
are the Construction Regulations.
The temporary nature of construction sites makes them one of the most
dangerous places to work. These regulations are made under the Health and
Safety at Work Act 1974 and are designed specifically to promote safety at
work in the construction industry. Construction work is defined as any building or civil engineering work, including construction, assembly, alterations,
conversions, repairs, upkeep, maintenance or dismantling of a structure.
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Advanced Electrical Installation Work
Safety First
Head protection
●
●
16
The Construction Regulations
require everyone working on a
construction site to wear head
protection
This includes electricians.
The general provision sets out minimum standards to promote a good level
of safety on site. Schedules specify the requirements for guardrails, working platforms, ladders, emergency procedures, lighting and welfare facilities. Welfare facilities set out minimum provisions for site accommodation:
washing facilities, sanitary conveniences and protective clothing. There is
now a duty for all those working on construction sites to wear head protection, and this includes electricians working on site as sub-contractors.
Building Regulations – Part P 2006
The Building Regulations lay down the design and build standards for construction work in buildings in a series of Approved Documents. The scope
of each Approved Document is given below:
Part A
Part B
Part C
Part D
Part E
Part F
Part G
Part H
Part J
Part K
Part L
Part M
Part N
Part P
structure
fire safety
site preparation and resistance to moisture
toxic substances
resistance to the passage of sound
ventilation
hygiene
drainage and waste disposal
combustion appliances and fuel storage systems
protection from falling, collision and impact
conservation of fuel and power
access and facilities for disabled people
glazing – safety in relation to impact, opening and cleaning
electrical safety.
Part P of the Building Regulations was published on 22 July 2004, bringing domestic electrical installations in England and Wales under building
regulations control. This means that anyone carrying out domestic electrical installation work from 1 January 2005 must comply with Part P of
the Building Regulations. An ammended document was published in an
attempt at greater clarity and this came into effect on 6 April 2006.
If the electrical installation meets the requirements of the IEE Regulations
BS 7671, then it will also meet the requirements of Part P of the Building
Regulations, so no change there. What is going to change under Part P is
this new concept of ‘notification’ to carry out electrical work.
NOTIFIABLE ELECTRICAL WORK
Any work to be undertaken by a firm or individual who is not registered
under an ‘approved competent person scheme’ must be notified to the
Local Authority Building Control Body before work commences. That is,
work that involves:
●
the provision of at least one new circuit,
●
work carried out in kitchens,
Statutory regulations and safe working procedures
●
●
work carried out in bathrooms,
work carried out in special locations such as swimming pools and
hot air saunas.
Upon completion of the work, the Local Authority Building Control Body
will test and inspect the electrical work for compliance with Part P of the
Building Regulations.
NON-NOTIFIABLE ELECTRICAL WORK
Work carried out by a person or firm registered under an authorized
Competent Persons Self-Certification Scheme or electrical installation
work that does not include the provision of a new circuit. This includes
work such as:
●
●
●
●
●
●
replacing accessories such as socket outlets, control switches and
ceiling roses;
replacing a like for like cable for a single circuit which has become
damaged by, for example, impact, fire or rodent;
re-fixing or replacing the enclosure of an existing installation component provided the circuits protective measures are unaffected;
providing mechanical protection to existing fixed installations;
adding lighting points (light fittings and switches) to an existing circuit,
provided that the work is not in a kitchen, bathroom or special location;
installing or upgrading the main or supplementary equipotential
bonding provided that the work is not in a kitchen, bathroom or special location.
All replacement work is non-notifiable even when carried out in kitchens,
bathrooms and special locations, but certain work carried out in kitchens,
bathrooms and special locations may be notifiable, even when carried
out by an authorized competent person. The IEE have published a guide
called the Electricians’ Guide to the Building Regulations which brings clarity to this subject. In specific cases the Local Authority Building Control
Officer or an approved Inspector will be able to confirm whether Building
Regulations apply.
Failure to comply with the Building Regulations is a criminal offence and
Local Authorities have the power to require the removal or alteration of
work that does not comply with these requirements.
Electrical work carried out by DIY home-owners will still be permitted after
the introduction of Part P. Those carrying out notifiable DIY work must first
submit a building notice to the Local Authority before the work begins.
The work must then be carried out to the standards set by the IEE Wiring
Regulations BS 7671 and a building control fee paid for such work to be
inspected and tested by the Local Authority.
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Advanced Electrical Installation Work
COMPETENT PERSONS SCHEME
The Competent Persons Self-Certification Scheme is aimed at those who
carry out electrical installation work as the primary activity of their business. The government has approved schemes to be operated by BRE
Certification Ltd., British Standards Institution, ELECSA Ltd., NICEIC
Certification Services Ltd., and Napit Certification Services Ltd. All the
different bodies will operate the scheme to the same criteria and will be
monitored by the Department for Communities and Local Government,
formally called the Office of the Deputy Prime Minister.
Those individuals or firms wishing to join the Competent Persons Scheme
will need to demonstrate their competence, if necessary, by first undergoing training. The work of members will then be inspected at least once
each year. There will be an initial registration and assessment fee and then
an annual membership and inspection fee.
18
The Electricity Safety, Quality and Continuity
Regulations 2002
The Electricity Safety, Quality and Continuity Regulations replaces the
Electricity Supply Regulations 1988. They are statutory regulations
which are enforceable by the laws of the land. They are designed to
ensure a proper and safe supply of electrical energy up to the consumer’s
terminals.
These regulations impose requirements upon the regional electricity
companies regarding the installation and use of electric lines and equipment. The regulations are administered by the Engineering Inspectorate
of the Electricity Division of the Department of Energy and will not normally concern the electrical contractor except that it is these regulations
which lay down the earthing requirement of the electrical supply at the
meter position.
The regional electricity companies must declare the supply voltage and
maintain its value between prescribed limits or tolerances.
The government agreed on 1 January 1995 that the electricity supplies in
the United Kingdom would be harmonized with those of the rest of Europe.
Thus the voltages used previously in low voltage supply systems of 415 and
240 V have become 400 V for three-phase supplies and 230 V for singlephase supplies. The permitted tolerances to the nominal voltage have also
been changed from ⫾6% to ⫹10% and ⫺6%.
The next proposed change is for the tolerance levels to be adjusted to
⫾10% of the declared nominal voltage. (IEE Regulations Appendix 2:14).
The frequency is maintained at an average value of 50 Hz over 24 hours so
that electric clocks remain accurate.
Regulation 29 gives the area boards the power to refuse to connect a supply to an installation which in their opinion is not constructed, installed
and protected to an appropriately high standard. This regulation would
Statutory regulations and safe working procedures
only be enforced if the installation did not meet the requirements of the
IEE Regulations for Electrical Installations.
The Electricity at Work Regulations 1989
This legislation came into force in 1990 and replaced earlier regulations
such as the Electricity (Factories Act) Special Regulations 1944. The regulations are made under the Health and Safety at Work Act 1974, and enforced
by the HSE. The purpose of the regulations is to ‘require precautions to be
taken against the risk of death or personal injury from electricity in work
activities’.
Section 4 of the Electricity at Work Regulations (EWR) tells us that ‘all
systems must be constructed so as to prevent danger …, and be properly maintained. … Every work activity shall be carried out in a manner
which does not give rise to danger. … In the case of work of an electrical
nature, it is preferable that the conductors be made dead before work
commences’.
The EWR do not tell us specifically how to carry out our work activities and
ensure compliance, but if proceedings were brought against an individual
for breaking the EWR, the only acceptable defence would be ‘to prove that
all reasonable steps were taken and all diligence exercised to avoid the
offence’ (Regulation 29).
An electrical contractor could reasonably be expected to have ‘exercised
all diligence’ if the installation was wired according to the IEE Wiring
Regulations and this is confirmed in the 17th Edition at Regulation 114 (see
below). However, electrical contractors must become more ‘legally aware’
following the conviction of an electrician for manslaughter at Maidstone
Crown Court in 1989. The Court accepted that an electrician had caused
the death of another man as a result of his shoddy work in wiring up a central heating system. He received a 9 month suspended prison sentence.
This case has set an important legal precedent, and in future any tradesman or professional who causes death through negligence or poor workmanship risks prosecution and possible imprisonment.
DUTY OF CARE
Definition
Everyone has a duty of care but not
everyone is a duty holder. The person
who exercises ‘control over the whole
systems, equipment and conductors’
and is the Electrical Company’s representative on site, is the duty holder.
The Health and Safety at Work Act and the Electricity at Work Regulations
(EWR) make numerous references to employer and employees having a ‘duty
of care’ for the health and safety of others in the work environment. In this
context the EWR refer to a person as a ‘duty holder’. This phrase recognizes
the level of responsibility which electricians are expected to take on a part of
their job in order to control electrical safety in the work environment.
Everyone has a duty of care but not everyone is a duty holder. The regulations recognize the amount of control that an individual might exercise over
the whole